1. Field of the Invention
The invention relates to a power source apparatus and a pulse generating apparatus which can suppress a loss of electronic equipment in a standby mode.
2. Description of the Related Arts
Hitherto, a standby mode is provided for a TV apparatus and a VTR apparatus. The standby mode is a mode in which the operation of a main circuit of the apparatus is stopped. For example, the standby mode is a mode in which when some operation is instructed by a remote controller, such an instruction is received, thereby enabling the operation corresponding to the instruction to be immediately performed.
In the standby mode, a method whereby a power source to be supplied is stopped and only a receiving unit for receiving the instruction of some operation is made operative, thereby suppressing an electric power consumption is considered. At this time, for example, a capacitor is used for making only the receiving unit operative. A power source is supplied at a predetermined cycle in order to keep a voltage/current of the capacitor to a predetermined value or more. As mentioned above, a timer or an oscillator (OSC) is used for supplying the power source at a predetermined cycle.
However, since the timer or oscillator (OSC) is used, a large electric power consumption is expended, so that there is a problem such that the electric power consumption in the standby mode cannot be sufficiently suppressed.
It is, therefore, an object of the invention to provide a power source apparatus and a pulse generating apparatus which can sufficiently suppress an electronic power consumption in the standby mode.
According to the invention disclosed in claim 1, there is provided a power source apparatus having a standby mode, comprising pulse generating means to which an AC power source is supplied and which intermittently generates pulses by time constant means constructed by a resistor and a capacitor, wherein by turning on/off the power source by the pulses from the pulse generating means, the power source in the standby mode is formed.
According to the invention disclosed in claim 8, there is provided a pulse generating apparatus to which an AC power source is supplied, comprising: a time constant circuit constructed by a resistor and a capacitor; first voltage detecting means for detecting a voltage which is supplied; switching means; and second voltage detecting means for detecting a voltage which is outputted from the switching means, wherein when a voltage higher than a first reference voltage is detected by the first voltage detecting means after a time constant set by the time constant means, the switching means is turned on, and when a voltage lower than a second reference voltage is detected by the second voltage detecting means, the switching means is turned off, thereby intermittently generating pulses.
The above and other objects and features of the present invention will become apparent from the following detailed description and the appended claims with reference to the accompanying drawings.